New Functionality

A new physics interface for Heat Transfer in Porous Media accounts for the effect
of a tortuous path, which results in the additional convective thermal dispersion
perpendicular to the main flow. The temperature field is thus more accurately
described compared to previous implementations.

A new physics interface for Radiation in Participating Media introduces the
effect of absorption of energy in a media subjected to radiation. The radiation
pattern from one surface to another then depends on the media present between the
radiating or reflecting surfaces.

The new physics interface for Low-Reynolds Number k-ε Turbulence Model yields
a higher accuracy in the description of the flow and heat transfer close to walls.

The new Open Boundary condition is useful for modeling an open boundary where
heat can flow out from the domain or into the domain with a specified exterior
temperature.

Backward Compatibility

Highly conductive layers in the interface between a solid and a fluid are not yet fully
implemented and give incorrect results when used in combination with wall functions
in turbulent flow. This is caused by the incorrect definition of the wall temperature as
the average of the solid and fluid temperature in these physics interfaces.

In some case, you can correct this in equation view. Please contact technical support if
you run into problems with such a model.

Turbulent Flow with Wall Functions and Surface-to-Surface Radiation

The wall temperature is incorrectly defined as the average of the fluid temperature and
the solid temperature in version 4.0. This gives incorrect results when using wall
functions in combination with surface-to-surface radiation.

In some case, you can correct this in equation view. Please contact technical support if
you run into problems with such a model.

K-ω Turbulance Model

The k-ω turbulence model physics interface is not yet implemented in version 4.0. It
is planned for the CFD Module in version 4.1.

The Low-Reynolds k-ε turbulence model interface is an excellent alternative for higher
accuracy in models including confined flows.